This number is a composite.

+ The smallest composite Mersenne number with a prime exponent (211 - 1 = 23 x 89).

+ The smallest strong base-2 pseudoprime. [Terr]

+ The 16th century French philosopher, Charles de Bouvelles, perhaps due to difficulties in division, cited falsely 2047 as prime.

+ The smallest Woodall number (2047 = 8*2^8-1) with a Woodall prime as its smallest factor.

+ The smallest Mersenne semiprime. [Gupta]

+ The next brilliant number year (23 * 89). [Gaydos]

(There is one curio for this number that has not yet been approved by an editor.)

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